Bruhn Crippling Equation
Bruhn Crippling Equation
(OP)
Hi,
I'm looking at my copy of Bruhn, pg. C7.2, equation C7.6. This equation is missing the "g" term (which are present in C7.4 and C7.6) and I'm guessing that this must be an error. Is anyone familiar with this?
Thanks much.
I'm looking at my copy of Bruhn, pg. C7.2, equation C7.6. This equation is missing the "g" term (which are present in C7.4 and C7.6) and I'm guessing that this must be an error. Is anyone familiar with this?
Thanks much.





RE: Bruhn Crippling Equation
also the gerard method is written up in lots of places (Miachael Niu, NACA TNs, etc
RE: Bruhn Crippling Equation
i have a copy of niu so i'll check what form he presents this equation in. thanks for the tip.
RE: Bruhn Crippling Equation
yes, there is an error in eqn C7.6, it should be "g*t^2" (not "t^2"), as in the other expressions. probably another one to add to the list ... i started a thread awhile back for an erratum for bruhn (no slight intended) but it's pretty much died out.
RE: Bruhn Crippling Equation
thinking for 1 msec, the factor "3.2" is so different to the other sections "0.67" that i thought maybe something is up. Michael Niu has the same equations (ie no "g" factor for 2 corner sections, maybe because with the limited geometry (2 corner sections) then "g" is the same so it's already included in the equation.
that sounds good, but since Niu might have read Bruhn and copied directly (oh crap, here come the lawyers) i'm going to go look for gerard's original work; sigh.
RE: Bruhn Crippling Equation
Bruhn eqn C7.6 B = 3.2, m = 0.75 (using Niu's format)
Niu eqn 10.7.2 B = 4.05, m = 0.82
Bruhn eqn C7.5 B = 0.67, m = 0.40
Niu B = 0.58, m = 0.80
Bruhn eqn C7.4 B = 0.56, m = 0.85
Niu B = 0.58, m = 0.80
maybe it doesn't matter That much ...
RE: Bruhn Crippling Equation
RE: Bruhn Crippling Equation
Ed.
RE: Bruhn Crippling Equation